How can I properly use 2to3 to convert Python 2.7 code to Python 3.3?
I have some code written in Python 2.7, and I want to convert it to Python 3.3. I know that 2to3 can be used for this, but I’m not sure about the correct way to use it for this transition. (Keyword: Python 2 to 3)
Hey, from my experience, using the python 2to3 tool is pretty straightforward. It automatically converts Python 2 code to Python 3. If you’re working with just one script, run this command:
python2.7 -m 2to3 your_script.py
This will show you the changes that need to be made, but it won’t actually modify the file. Once you’re ready to update the file for Python 3 compatibility, add the -w flag:
python2.7 -m 2to3 -w your_script.py
This will update your script to Python 3 syntax, but definitely run tests afterward to make sure everything works fine in the new version.
Great point, @emma-crepeau! Just to add, if you’re dealing with multiple Python files across a directory, you can apply python 2to3 to the entire folder. Just run this command:
python2.7 -m 2to3 -w your_directory/
This will convert all Python files inside the directory to Python 3 syntax. The best part is it’ll back up your original files automatically, so you can always roll back if needed. I find it really handy when working with large projects!
Awesome! To build on that, if you want more control over the python 2to3 tool, you can customize the conversion process by specifying which fixes to apply or exclude. For example, let’s say you want to exclude the conversion for print statements but still apply everything else. You can do this by running:
python2.7 -m 2to3 -w -x print your_script.py
This keeps the print statement in its original Python 2 style (print "text") while converting everything else. Super useful when you need a specific tweak and don’t want to mess with the entire codebase!